Differential governor for boiler feed pumps



Apr, 17, 1923. 11 41525223 0. J. SMITH DIFFERENTIAL GOVERNOR FOR BOILER FEED PUMPS Filed 001;. 12, 1921 Q, C0743 L7 37711772,

Patented Apia 31?, W23,

EARL l. SIdITH, OF INDIANA HALRBQR, INIDMG'A,

DIFFERENTIAL GGVEBNOR FOR BOILER FEED PUEMPd.

a lication filed @ctober 11 a, 1921. serial no. comet.

To all whom it may concern:

Be it known that l, CARL J. SMITH, a citizen of the United States, residing at Indiana Harbor, in the county of Lake and State of 5 Indiana, have invented a. new and useful Improvement in Differential Governors for Boiler Feed Pumps, of which the following is a specification.

My invention relates, more particularly,

to mechanism provided in connection with steam-operated pumps for pumping water into boilers-wherein steam is being generated and operating to maintain at all times, regardless of variations in the pressure of steam supplied to the pumping apparatus, a

predetermined amount of pressure of water to the boiler in excess of the boiler pressure; and my-object, generally stated, is to provlde a novel and simple construction for producing excess pressure as above stated which shall be positive in action under continued I use. More specifically my objects are to eliminate counterweights, levers, springs,

pilot valves and stufling boxes, which are a source of expense and trouble to maintain:

to render the device sensitive in operation;

and'to eliminate appreciable friction.

Referring to the accompanying drawing: Figure 1 is a view, somewhat in the nature 30 of a diagram, showing a. boiler, together with a water-supplying means therefor embodying my improvements; and Figure 2,

a View in vertical sectional elevation of the regulating mechanism employed as a part of the said apparatus and constructed in accordance with my invention. 1

In the arrangement f'shown, a. boiler to be supplied with feed water is represented at 3,, and the pump for pumping water lnto the boiler 3, is represented at 4, the inlet of the pump being represented, at 5 and the pipe which leads from the outlet of the pump into the interior. of the boiler for supplying water thereto, at 6. The steam-driven motor for operating the pump 4 is re resented at 7 its rotary element (not shownl being represented as connected with the rotaryelement (lpot shown) of the pump, by means of a s aft 8. Steam from the boiler 3 is supplied to the motor 7 for operating it, through the pipe 9 which opens at one end into the boiler and at its opposite end into the inlet of the motor 7.

The pipe 9 has interposed therein a valve mechanim represented at 11, this valve com-' prising a casing 12, the inlet end oil which is represented at13 and the outlet at 16C. The casing 12 is shown as formed with an internal hollow extension 15, the interior of which communicates with the outlet 14, the upper and lower wall portions of this extension containing apertures which communicate with the inlet and outlet 13 and 14 and are lined with valve-seat-z'forming bushings 16 and 1? afiording the annular valve 653 seats 18 and 19. The valve proper of the valve structure 11 is represented at 20, this valve being shown as oil the balanced type and formed as a hollow structure affording annular valve-seat-engaging disks 21 and 22 W for cooperation with the seats 18 and 19, respectively, the wall of the valve device 20 containing at intervals slots 23 so arranged that as soon as the valve device 20 leaves the seats 18 and 19 the inlet 13 will be in commure nication with the outlet 14 below the seat 19. The upper end of the valve device 20 is of spider construction, as shown, so that as soon as the valve leaves its seats communication between'thc inlet 13 and outlet 14 so will also be eflected above the disk 21, thereby rendering the valve balanced. The valve casing 12 is provided with a depending tubular member 24 which opens at its upper end into the interior of he valve casing and as at its lower end into the upper end of a diaphragm-casing 25, containing a diaphragm 26 of any suitable construction which latter divides the interior of the casing 25 into upper and lower chambers 27 no and 28, respectively, which are maintained out of communication with each other. The valve device 20 is provide-d with a depending stem 29 connected at its upper end with the valve device, and at its lower end to the 5 diaphragm 26, the stem 29 extending freely through the tube 24 and the passage leading from the latter into the chamber 27, to permit of the exertion, against the upper surface of the diaphragm 26, of the steam pres-' we sure at the inlet 13 of the valve structure. The chamber 28 communicates with the upper end of a pipe 30 rovided at its lower end with a laterally-dc ected portion 31 and at the extremity of this deflected portion with my. an upwardly-extending portion 32 which opens into a closed receptacle 33, through the bottom of the latter the top of this receptacle being equipped with a pipe 34 which opens into the interiorof the receptacle and we iii connects with the pipe 6. The receptacle 33 is charged with any suitable fluid, preferably mercury, which is represented at 35.

The operation of the apparatus is as follows: Steam generated in the boiler 3 and entering the inlet 13- of the valve 11 flows past the valve device, and thence through the outlet 14: and to the motor 7 for driving the motor, and as the chamber 2? is in communication with the inlet portion. of the casing 12 the steam pressure at the inlet 13 is also exerted against the upper surface of the diaphragm 26. The pressure of the water discharged through the pipe 6 from the pump 4; into the boiler 3 is at the same time exerted upon the top of the fluid 35 in receptacle 33 with result of forcing this fluid into the chamber 28 of the diaphragm casing 25 and exerting an upward pressure on the diaphragm. As the pressure of steam supplied through the pipe 9 increases, the valve device 20 will he forced down lay the increase of steam pressure on the upper side of the diaphragm E26 and the volume of steam supplied to the motor 7 will be increased, the valve in lowering acting against the column of fluid 35 and tending to force it into the receptacle 33, and as the pump 1- increases its speed due to the increase in the amount of steam. supplied to the motor 7, the pressure of the discharge from the pump a will be increased and this pressure will react against the fluid 35 in the receptacle 33, and consequently against the under side of the diaphragm. 26, until the pressure against the opposite sides of the diaphragm is balanced.

chould the steam pressure generated in the boiler 3 become decreased, the pressure upon the upper side of the diaphragm will become reduced, and consequently the fluid 35 will rise in the chamber 28 and the valve 20 will be moved toward closed position, until the pressure of the discharge from the pump 4 in reducing permits of the reverse movement of the liquid 35, viz,'toward the receptacle 33, until the pressures above and below the diaphragm 26 become balanced' It will be understood from the foregoing that by the arrangement shown the discharge pressure from the pump is maintained at a constant excess over the steam pressure regardless of the increase or decrease of the pressure generated in the boiler 3. the change in steam pressure being; immediately communicated to the pump discharge pressure by the valve 11. automatically regulating the supply of steam to the pump operating mechanism 7.

Furthermore, it will be understood that the degree of excess of the pump pressure over the steam pressure will be dependent upon the height at which the casing 25 extends, relative to the receptacle 33, or, in other words, upon the height of the column of liquid in. the pipe 30 and chamber 28, increasing the height of the casing 25 above the receptacle 33 increasing the constant excess of pump discharge pressure over the steam pressure and decreasing the height at which this casing extends above the receptacle 33, reducinc the degree of the pump discharge pressure relative to the steam pressure.

l'i hile l have illustrated and described a particular construction embodying in invention, i do not wish to be understood as intending to limit it thereto as the same may be variously modified and altered without departing from the. spirit thereof.

l/Vhat I claim as new, and desire to secure by Letters Patent, is:

1. In apparatus of the character set forth. the combination of a source of fluid pressure, means operated from said source for generating pressure, and means for main taining, under variations of pressure of the fluid from said source, the pressure generated by said first-named means at a constant excess over the pressure of fluid supplied from said source, comprising a column of fluid, the upper portion of which is subiected to the pressure from. said source and the lower portion of which is subjected to the pressure generated by said first-named means, and valve means for controlling; the How of fluid pressure from said source to said first-named means, controlled by said column of liquid,

2. In apparatus of the character set forth, the combination of asource of fluid pressure, means operated from said source for generating pressure, and means for maintaining, under variations of pressure of the fluid from said source, the pressur generated bv said first-named means at. a constant excess over the pressure of fluid supplied from said source, comprising a column of fluid, the upper portion of which is subjected to the pressure from said source and the lower portion of which is subiected to the pressure generated by said first-named means, and a balanced valve device for controlling the fluid pressure from said source to said first-named means, controlled by said column of liquid. I

3. In apparatus of the character set forth. the combination of a source of fluid pressure. means operated from said source for generating pressure, and means for maintaininu. under variations of pressure of the fluid from said source. the pressure generated bv said first-named means at a constant excess over the pressure of fluid supplied from said source, comprising a column of fluid. a diaphragm at the upper end of said column. the lower portion of said column being subjected to the pressure generated by said first named means, and valve means for controlling the flow of fluid pressure from said pin source to said first-named means, operated by said diaphragm.

In apparatus of the character set forth, the com ination of a source of fluid pressure, means operated from said source for generating pressure and means for mainrtaining, under variations of pressure of the" fluid from said source, the pressure generated by said first-named means at a constant excess over the pressure of fluid supplied from said source, comprising a column of fluid, a diaphragm at the upper end of said column, the lower portion of said column being subjected to the pressure generated by said first-named means, and a balanced valve device for controlling the flow of fluid pressure from said source to said first-named means, operated by said. diaphragm.

In apparatus of the character set forth, the combination of a steam boiler, pumping means for supplying Water to the boiler, a pipe leading from said boiler to said pumping means for supplying steam to the latter for its operation, a column of fluid the upper portion of Which is subjected to the steam pressure and the lower portion of which is subjected to thepump discharge pressure, and valve means for controlling the flow of steam to said pumping means, controlled by said column ofv liquid.

In apparatus of the character set forth, the combination of a steam boiler, pumping means for supplying water to the boiler, a pipe leading from said boiler to said pump- -subjected to the ing means for supplying steam to the latter for its operation, a column of fluid the upper portion of which is subjected to the steam pressure and the lower portion of which is pump discharge pressure, and a balanced valve device for controlling the flow of steam to said pumping means, controlled by said column of liquid.

' In apparatus of the character set forth, the combination of a steam boiler, pumping means for supplying water to the boiler, a pipe leading fromsaid boiler to said pum ing means for supplying steam to the latter for its operation, a column of fluid, a diaphragm at the upper end of said column, the lower portion of said column being subpump discharge pressure, and valve means operated by said diaphragm for controlling the flow of steam to said pumping means.

In apparatus of the character set forth, the combination of a steam boiler, pumping means for supplying Water to the boiler, a pipe leadingifrom said boiler to said pumping means for supplying steam to the latter for its operation, a column of fluid, a dia-' phragm at the upper end of said column, the lower portion of said column being subjected to the pump discharge pressure, and a balanced valve device for controlling the flow of steam to said pumping means, operated by said diaphragm.

CARL .i. SMITH. 

